Many Veterans with lower-limb amputations have difficulty managing their prosthetic socket fit due to reduced sensation in their residual limb, cognitive issues, or insufficient training. Although they are instructed to compensate for changes in residual limb volume throughout the day using prosthetic socks, many Veterans spend large portions of the day with a poorly fitting prosthetic socket, which can lead to numerous skin problems, discomfort, and pain. The goal of this project is to develop and test a socket- fit sensing system that can adapt to patient-specific changes in limb volume and can help Veterans self-manage their socket fit during post-amputation rehabilitation care. The socket-fit sensing system can detect when the Veteran is wearing too few or too many socks and can discretely alert the Veteran when they need to add or remove prosthetic socks. In this project, we will pursue the following two specific aims: 1) refine the socket-fit sensing system and 2) test socket-fit-detection algorithms. We will refine the system using feedback from experienced Veteran prosthesis users and clinicians, and we will test the system with three Veterans during their post-amputation rehabilitation care. This project will create an easy-to-use tool to help Veterans with lower-limb amputations self-manage prosthetic socket fit. This tool will be especially beneficial for Veterans at an early stage in their rehabilitation and will help reduce preventable pain, discomfort, and skin issues common with poor socket-fit. We believe this project will enhance Veteran engagement with self-managing socket fit and ultimately will increase prosthesis use and community participation.